Deck 11: The Knee Complex

Question 1

Describe the congruency of the tibiofemoral joint.What factors add to or detract from stability?

Answer 1

The tibiofemoral (knee)is incongruent due to the large surface of the femoral condyles and the relatively small and flat surface of the tibial facets.On both the femur and the tibia,the medial facet is slightly larger than the lateral,a factor that influences the locking mechanism of the knee.

Question 2

What muscle group would you strengthen to provide dynamic stability for the loss of stability from a torn anterior cruciate ligament (ACL)?

A) Quadriceps muscles
B) Adductor muscles
C) Hamstring muscles
D) Gluteal muscles

Answer 2

C

Question 3

Which of the following best describes the screw home mechanism of the tibiofemoral joint during open kinetic chain movement?

A) Lateral rotation of the femur on the tibia occurring at 90^o knee flexion to lock the tibiofemoral joint in its close-packed position
B) Medial rotation of the tibia on the femur occurring at 60^o knee flexion to lock the tibiofemoral joint in its close-packed position
C) Lateral rotation of the tibia on the femur occurring at 0^o knee flexion to lock the tibiofemoral joint in its close-packed position
D) Medial rotation of the femur on the tibia occurring at 45^o knee flexion to lock the tibiofemoral joint in its close-packed position

Answer 3

C

Question 4

Which facet(s)of the patella are subject to the earliest degenerative changes under normal conditions? Why?

Question 5

Which of the following describes the effect on the lumbar spine of a subject standing in excessive bilateral genu recurvatum?

A) Compensatory increase in lumbar lordosis
B) Compensatory increase in lumbar kyphosis
C) Compensatory increase in thoracic lordosis
D) Compensatory increase in thoracic kyphosis

Question 6

Which of the following structural abnormalities will contribute to an increased Q-angle?

A) Femoral retroversion
B) Tibial medial torsion
C) Femoral anteversion
D) Tight adductor muscles

Question 7

Which of the following,if present,may cause an increase in the normal Q-angle?

A) Genu valgum
B) A narrow pelvis
C) Medially rotated pelvis
D) Femoral retroversion

Question 8

Which structure is a stabilizer of the patella in the transverse plane?

A) Patellar tendon
B) Quadriceps tendon
C) Patellotibial ligaments
D) Iliotibial band

Question 9

Which ligaments are responsible for medial-lateral stability of the knee joint? To which compartment do they belong?

Question 10

A patient injured his medial meniscus and structures attached to the medial meniscus.Which of the following best describes additional structures that may be injured?

A) Posterior cruciate ligament (PCL),semimembranosus tendon,and quadriceps expansion
B) Lateral collateral ligament (LCL),semitendinosus tendon,and posterior meniscofemoral ligaments
C) Medial collateral ligament (MCL),semimembranosus tendon,and anterior cruciate ligament
D) Anterior cruciate ligament (ACL),semitendinosus tendon,and fibrous expansion from the popliteus

Question 11

What are the dynamic stabilizers of the knee,and in what plane do they contribute to stability?

Question 12

During closed kinetic chain knee extension,the menisci are pushed ________________by the femoral condyles and pulled anteriorly by ____________________.

A) posteriorly,semimembranosus muscle
B) posteriorly,gracilis muscle
C) anteriorly,quadriceps expansion and patellofemoral ligament
D) anteriorly,popliteus muscle and coronary ligaments

Question 13

What muscle is primarily responsible for unlocking the tibia when flexing the knee?

A) Sartorius
B) Biceps femoris
C) Popliteus
D) Plantaris

Question 14

Identify the bursae of the knee joint.Which of these are generally separate from and which are part of the capsule?

Question 15

Passive insufficiency of which knee joint muscle would limit knee flexion?

A) Rectus femoris
B) Biceps femoris
C) Popliteus
D) Vastus lateralis

Question 16

An increased valgus position (genu valgus)of the knee will cause increased compressive forces on the ________________side of the tibiofemoral joint and place tensile forces on the ________________ligament.

A) medial,medial collateral
B) medial,lateral collateral
C) lateral,medial collateral
D) lateral,lateral collateral

Question 17

Which of the following best describes the ligament(s)that provide(s)the most resistance to tensile forces in 30° of closed kinetic chain flexion of the tibiofemoral joint?

A) Anterior cruciate ligament (ACL)
B) ACL and posterior cruciate ligament (PCL)
C) Medial collateral ligament (MCL)and lateral collateral ligament (LCL)
D) PCL,MCL,and LCL

Question 18

A person assumes a squat position to lift a heavy box.As the person assumes a fully upright position,the patella will move in two directions.Which of the following best describes the movement of the patella during this activity?

A) From lateral  medial  lateral and from cranial  caudal
B) From medial  lateral  medial and from cranial  caudal
C) From lateral  medial  lateral and from caudal  cranial
D) From medial  lateral  medial and from caudal  cranial

Question 19

Which of the following describes the movement of the menisci during closed kinetic chain medial rotation of the tibiofemoral joint?

A) Medial meniscus moves posteriorly; lateral meniscus moves anteriorly.
B) Medial meniscus moves anteriorly; lateral meniscus moves posteriorly.
C) Medial meniscus moves superiorly; lateral meniscus moves posteriorly.
D) Medial meniscus moves anteriorly; lateral meniscus moves superiorly.

Question 20

Describe the patellofemoral articulation,including the number and shape of the surfaces.

Question 21

Which aspect of the knee joint is most prone to injury? Why is this true,and what structures are most commonly involved?

Question 22

Why is ascending stairs commonly cited as producing knee pain? Relate this to patellofemoral joint compression.